Sheet metal pipe tau



Feb. 26, 1935. KUEHN 1,992,312

SHEET METAL PIPE T Filed Feb. 16, 1935 INVENTOR.

Patented Feb. 26, 1935 Steel C l `tion* of Delaware f ompany, Milwaukee, Wis., a corpora- This invention relates to an improvement in sheetA metalzpipeTfs and may be employed in furnace pipe or in stove pipe and in fact Wherever it is desirable to employ a sheet metal One of the objects of the invention is to provide a sheet metal pipe T of this character in which the walls of the T at the intersection of the axial and transverse or lateral passages are sloped or flared whereby to facilitate the passage of gases through the T and hence assure better draft. The resistance which the T presents to the passage of gas therethrough is minimized and tendency of the T to cause disturbing currents in the gases due to the abrupt change of direction of flow is avoided.

Another object of the invention is to provide a T of this character which is substantially airtight and yet is of enhanced strength and rigidity. The use of rivets is avoided and preferably the meeting edges of the single piece of metal which makes up the body of the T are seamed or otherwise effectively united.

Other objects and advantages resideV in certain novel features of the construction, arrangement and combination of parts which will be hereinafter Vmore fully described and particularly pointed out in the apended claims, reference being had to the accompanying drawing, forming a part of this specification, and in which:

Figure 1 is a View in side elevation showing a metal pipe T embodying the present invention;

Figure 2 is a View in end elevation further illustrating the T with a portion broken away and shown in section for the sake of illustration;

Figure 3 is a fragmentary view in section taken on line 3-3 of Figure 1;

Figure 4 is a similar view in vertical section taken on line 4-4 of Figure 1;

Figure 5 is a similar view in horizontal cross section taken on line 5--5 of Figure 2; and

Figure 6 is a group view in plan showing the blanks from which the body of the T and collars therefor are formed.

Referring to the drawing, it will be seen that the sheet metal pipe T embodying the present invention comprises a, body portion 1 having a lateral extension 1ft intermediate its ends and collars 2, 3 and 4, the collars 2 and 3 being interconnected with the body portion at the ends of the axial passage therethrough and the collar 4 being interconnected with the lateral extension 1a at the outer end of the transverse lateral passage.

The body portion lof the T is formed up from a single piece sheet metal blank shown at B in Figure. Thefblank hascurved cut-outs or r` their edges united by seams 10 to form the j rounded or flaring end walls V9. Such bending or folding of the blank causes the edges 11 thereof to provide openings at the ends of the axial passage of the body portion of the T, which openings are of circular cross section whereas the edges 5 during this shaping or bending are made to form an opening of circular cross section at the outer end of the transverse passage through the lateral extension 1a of the T. At the ends of the axial passage, the peripheral edge of the body portion of the T is bent inwardly or flanged as indicated at 12 in Figure 3 and such flanged formation fits over and interlocks with the correspondingly outwardly bent flange structure'lS formed on the collar 2. A similar interconnection is provided between the opposite end of the body portion of the T and the collar 3. The lower end of the extension 1a of the body portion of the T which denes the opening at the lower end of the transverse passage is also similarly flanged or bent inwardly as indicated at 14 about a corresponding flange structure 15 provided on thecollar 4. The collars 2, 3 and 4 are formed from blanks C, D and E, the blanks being bent into circular form and having their meeting edges united by a seam 16 as illustrated in Figures 2 and 5.

By employing seams between the meeting edges of the blank forming the body of the T and between the meeting edges of the blanks forming the collars the use of rivets is avoided and a strong and substantially air-tight structure is had. The seams may be effectively locked by punching portions thereof sufficiently to deform the metal of the seam slightly as indicated at 17. In use, the T has the distinct advantage of assuring better draft therethrough, the flaring or sloping end'walls 9 offering minimum resistance to the passage of the gases from the transverse to the axial passage or vice versa. By capping one of the collars 2 or 3, the T may be used as an e1bow.` y

While possessing the advantages of light weight and durability the T is extremely simple Yio in its construction and may be manufactured with economy from materials and by means of facilities ordinarily available.

While Ihave shown and described one construction in which the invention may vbe embodied, it is to be understood that this construction has been selected merely for the purposes of illustrationvand that various changes in the size, shape and arrangement of the parts maybe made Without departing from the spirit of the invention or the scope of the vsubjoined claims.

The invention claimed is: Y g

1. A sheet metal pipe T comprising afbody 'portion made of a sheet metal blank having curved recesses at its ends and formed with extension tabs at its corners, said blank being bent and certain of saidtabs being securedtogether to form axial and transverse passages terminating in open ends of circular crossv sections, said body portion having a top portion Whose surface is deiined by straight elementsrunning between the peripheries of the upperrhalves of two of said openV ends, side portions whoseV surfaces are defined by two planes tangentially disposed to the peripheriesl of al1 ofsaid open ends, and

connecting portions Whose surfaces are defined by straight elements running between the peripheries of the lower halves of the two said open ends and respective halves of another open end.

portion made up of a sheet metal blank having curved recesses at its ends and formed with extensionV tabs at its corners, said blank being bent and certain of said tabs being secured to- I gether to form axial and transverse passages terminating in open ends of circular cross sectionsi said body portion having a surface defined by'three sections of a half cylinder inter- Y secting to form three circular cross sections, andv two planes tangent to all of saidv cross sections.

3. A sheet metal pipe T comprising a body portion made up of a sheet metal blank having curved Vrecesses at its ends and formed with extension tabs at its corners, said blank being bent and certain of said tabs being secured togetherv to form axial and transverse passages terminating in open ends of circular cross section. Y LOUISKUEHN.

2. A sheet metal pipe T comprising'a body 

